Reduced Graphene Oxide Supported Cobalt Bipyridyl Complex for Sensitive Detection of Methyl Parathion in Fruits and Vegetables

Herein, we are described a green route to prepare reduced graphene oxide supported cobalt inorganic complex nanocomposite (GRGO/[Co(bpy)(3)]) (bpy = 2,2'-bipyridine) through facile and wet chemical approach. The formation of the nanocomposite was confirmed through suitable physical and chemical characterization techniques. The GRGO/[Co(bpy)(3)] nanocomposite was coated on the pretreated glassy carbon electrode (GCE). The GCE/GRGO/[Co(bpy)(3)] modified electrode has excellent electrocatalytic ability towards methyl parathion reduction, while the overpotential drops drastically to -0.18 V (vs. Ag/AgCl). Moreover, the effect of concentration, scan rate and electrolyte pH were detail studied. Besides, the linear response range was 0.05-1700 mu M and the detection limit was 0.0029 mu M (S/N = 3) and the sensitivity was 1.8197 mu A mu M-1 cm(-2). Moreover, the fabricated electrode has high level of selectivity, which delivers satisfactory repeatability, reproducibility and stability. The sensing method was successfully demonstrated in real samples such as, tomato and apple samples.